Of the many translators who carried the Buddhist doctrine to China, Paramartha, a missionary-monk who arrived in China in AD 546, ranks as the translator par excellence of the sixth century. Introducing philosophical ideas that would subsequently excite the Chinese imagination to develop the great schools of Sui and T'ang Buddhism, Paramartha's translations are almost exclusively of Yogacara Buddhist texts on the nature of the mind and consciousness. This first study of Paramartha in a Western language focuses on the Chuan shih lun (Evolution of Consciousness), a text that reveals the outline of Paramartha's Yogacara thought. The study begins with a discussion of Paramartha's life, the historical and political context of the time in India and south China, and the roles of his main disciples in disseminating his work. It then describes Paramartha's treatment of Yogacarin views on language and the process of cognition, both central to this system of thought. The final chapter analyzes the history and content of the Chuan shih lun, and the book concludes with a new translation of the text, with extensive annotations.